Prior Art
Dynamic balance correcting apparatuses for correcting the unbalance of a rotating body, such as a rotor, have hitherto been known to achieve such a correction by placing a correcting agent (the so-called putty), for example, the composition now known publicly through disclosure by the Official Gazette for Patent Laid Open No. 63-92639, after measuring the state of dynamic unbalance of the rotating body, such as a rotor for a motor.
A dynamic balance correcting apparatus of the kind described above determines the position and amount of unbalance on the basis of the result of measurement of the state of unbalance in a rotating body (which is generally called "the work") and then discharging a prescribed amount of a correcting agent from a nozzle or the like on the basis of the position and amount of the unbalance so determined. After such a prescribed amount of the correcting agent is discharged, such an apparatus cuts off the correcting agent by means of an air cutting device or the like, thereby disconnecting the said correcting agent from the nozzle, and sticks the said correcting agent to the rotating body.
Now, such a correcting agent thus stuck to the unbalanced part of a rotating body protrudes in some cases from the prescribed limits of the outer dimensions of the rotating body. In case such a rotating body should be used as a rotor for a motor, it would cause such troubles as a failure in the rotation of the motor because of the interference which such a protruding part causes with the magnet at the side of the yoke or because of a failure in securing the dynamic balance of the rotor as the result of the falling off of the correcting agent.
Therefore, in order to prevent such troubles as those just described, a dynamic balance correcting apparatus for rotating body whereby the correcting agent attached to the rotating body can be thrust down to be secured in a fixed position been proposed (each in the Official Gazette for Patent Laid Open No. 62-203535 and the Official Gazette for Publication of Utility Model No. 63-39655). This dynamic balance correcting apparatus is provided with a pressing member soaked with fluid. The correcting agent cut off from the nozzle and stuck to the rotating body is pushed down by force with this pressing member, and the correcting agent thus stuck on the unbalanced part of the rotating body can be prevented thereby from protruding beyond the prescribed limits of the outer dimensions of the rotating body.
Problems with Existing Apparatuses
However, the existing dynamic balance correcting apparatuses for a rotating body, such as those described above, have a defect in that they fail to detect or to ascertain a protrusion of the correcting agent in case the securing of the correcting agent with the pressing member mentioned above is not complete, that is, in case the correcting agent still remains protruding from the prescribed limits of the outer dimensions of the rotating body. Moreover, the prior art apparatuses are likewise not capable of detecting or ascertaining any protrusion formed afresh of the correcting agent in consequence of the lack of thorough hardening in the correcting agent in the processes subsequent to this pressing process (namely, the process for verifying the ultimate state of balance and the hardening process of the correcting agent).
Therefore, the existing apparatuses require the workers to perform an inspection on all the units of the rotating body to check on the state of protrusion of the correcting agent by their manual work, which causes the problem that the working efficiency is deteriorated to a very considerable degree. In such a case, moreover, visual inspection performed by workers is necessarily liable to the occurrence of a lack of uniformity in the results of such inspection, which makes it difficult to guarantee any stable product quality.